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Expansion of CD4+CD28null T-lymphocytes is common in chronic heart failure (CHF) patients. Its ability to produce high levels of proinflammatory cytokines is probably the key role of these cells in CHF. IL-10 is a candidate for limiting CD4+CD28null T-lymphocyte responses, whereas tumour necrosis factor (TNF) is the cytokine most closely involved in the loss of CD28 expression. Serum levels of TNF and IL-10 were measured in 65 CHF patients (mean age, 65.2 ± 13.84 years). Patients with an IL-10/TNF ratio ≥1 had significantly lower levels of CD4+CD28null T-lymphocytes than those with a ratio <1. In vitro, IL-10 reduced the frequency of proliferative CD4+CD28null T-lymphocytes stimulated with anti-CD3. Pre-treatment with IL-10 before anti-CD3 stimulation was required for the cytokine to inhibit TNF production by CD4+CD28null T-lymphocytes. In addition to the previously described effect of IL-10 on HLA-DR and ICAM-1 expression, LFA-3 protein and mRNA levels were reduced in the presence of the cytokine in monocytes. IL-10 inhibition on CD4+CD28null T-lymphocytes may be mediated by a reduction in HLA class II and LFA-3 expression because blocking interactions with these costimulators has similar effects to those of IL-10 treatment. Moreover, costimulation through CD2/LFA-3 interaction is enough to induce proliferation and cytokine production in CD4+CD28null T-lymphocytes.
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BACKGROUND: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15-20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases. METHODS: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded. RESULTS: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5-528.7, P = 1.1 × 10-4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3-8.2], P = 2.1 × 10-4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1-2635.4], P = 3.4 × 10-3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3-8.4], P = 7.7 × 10-8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10-5). CONCLUSIONS: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old.
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COVID-19 , Interferón Tipo I , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , SARS-CoV-2 , Receptor Toll-Like 3/genética , Receptor Toll-Like 7 , AutoanticuerposRESUMEN
Faecalibacterium represents one of the most abundant bacterial groups in the human intestinal microbiota of healthy adults and can represent more than 10% of the total bacterial population, Faecalibacterium prausnitzii being the only recognized species up to the past year. Reduction in the abundance of F. prausnitzii in the human gut has been linked to several human disorders, such as Crohn's disease. In this study, we developed a strategy to modify the relative abundance of F. prausnitzii in fecal microbiotas as a means of evaluating its contribution to the immunomodulatory effect of intestinal microbiotas with different F. prausnitzii contents using a peripheral blood mononuclear cell (PBMC) model. We used a polyclonal antibody against the surface of F. prausnitzii M21 to capture the bacterium from synthetic and human fecal microbiotas using immunoseparation techniques. As a proof-of-principle study, the levels of immunomodulation exerted by microbiotas of healthy donors (HDs) with different relative abundances of F. prausnitzii, achieved with the above-mentioned immunoseparation technique, were evaluated in a PBMC model. For this purpose, PBMCs were cocultivated with the modified microbiotas or a pure culture of F. prausnitzii and, subsequently, the microbiota of Crohn's donors was added to the coculture. The cytokine concentration was determined, showing that our experimental model supports the anti-inflammatory effects of this bacterium. IMPORTANCE There is increasing interest in deciphering the contribution of gut microbiota species to health and disease amelioration. The approach proposed herein provides a novel and affordable strategy to probe deeply into microbiota-host interactions by strategically modifying the relative abundance of specific gut microbes, hence facilitating the study of their contribution to a given trait of the microbiota.
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Enfermedad de Crohn , Microbiota , Adulto , Humanos , Faecalibacterium prausnitzii , Leucocitos Mononucleares , Heces/microbiologíaRESUMEN
Background: We previously reported inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity in 1-5% of unvaccinated patients with life-threatening COVID-19, and auto-antibodies against type I IFN in another 15-20% of cases. Methods: We report here a genome-wide rare variant burden association analysis in 3,269 unvaccinated patients with life-threatening COVID-19 (1,301 previously reported and 1,968 new patients), and 1,373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. A quarter of the patients tested had antibodies against type I IFN (234 of 928) and were excluded from the analysis. Results: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7 , with an OR of 27.68 (95%CI:1.5-528.7, P= 1.1×10 -4 ), in analyses restricted to biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR=3.70 [95%CI:1.3-8.2], P= 2.1×10 -4 ). Adding the recently reported TYK2 COVID-19 locus strengthened this enrichment, particularly under a recessive model (OR=19.65 [95%CI:2.1-2635.4]; P= 3.4×10 -3 ). When these 14 loci and TLR7 were considered, all individuals hemizygous ( n =20) or homozygous ( n =5) for pLOF or bLOF variants were patients (OR=39.19 [95%CI:5.2-5037.0], P =4.7×10 -7 ), who also showed an enrichment in heterozygous variants (OR=2.36 [95%CI:1.0-5.9], P =0.02). Finally, the patients with pLOF or bLOF variants at these 15 loci were significantly younger (mean age [SD]=43.3 [20.3] years) than the other patients (56.0 [17.3] years; P= 1.68×10 -5 ). Conclusions: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old.
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Background: The clinical and epidemiological implications of abnormal immune responses in COVID-19 for latent tuberculosis infection (LTBI) screening are unclear. Methods: We reviewed QuantiFERON TB Gold Plus (QFT-Plus) results (36,709 patients) from July 2016 until October 2021 in Asturias (Spain). We also studied a cohort of ninety hospitalized patients with suspected/confirmed COVID-19 pneumonia and a group of elderly hospitalized patients with COVID-19 who underwent serial QFT-Plus and immune profiling testing. Results: The indeterminate QFT-Plus results rate went from 1.4% (July 2016 to November 2019) to 4.2% during the COVID-19 pandemic. The evolution of the number of cases with low/very low interferon-gamma (IFN-gamma) response in the mitogen tube paralleled the disease activity and number of deaths during the pandemic waves in our region (from March 2020 to October 2021). The percentages of positive QFT-plus patients did not significantly change before and during the pandemic (13.9% vs. 12.2%). Forty-nine patients from the suspected/confirmed COVID-19 pneumonia cohort (54.4%) had low/very low IFN-gamma response to mitogen, 22 of them (24.4%) had severe and critical pneumonia. None received immunosuppressants prior to testing. Abnormal radiological findings (P = 0.01) but not COVID-19 severity was associated with low mitogen response. Immune profiling showed a reduction of CD8 + T cells and a direct correlation between the number of EMRA CD8 + T-cells and IFN-gamma response to mitogen (P = 0.03). Conclusion: Low IFN-gamma responses in mitogen tube of QFT-Plus often occur in COVID-19 pneumonia, which is associated with a low number of an effector CD8 + T-cell subset and does not seem to affect LTBI screening; however, this abnormality seems to parallel the dynamics of COVID-19 at the population level and its mortality.
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COVID-19 , Tuberculosis Latente , Mycobacterium tuberculosis , Anciano , Biomarcadores , COVID-19/diagnóstico , COVID-19/epidemiología , Humanos , Interferón gamma , Ensayos de Liberación de Interferón gamma , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/epidemiología , Mitógenos , Pandemias , Prueba de TuberculinaRESUMEN
Understanding how older people respond to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical if we are to confront the coronavirus disease 2019 (COVID-19) pandemic and establish effective vaccination strategies. Immunosenescence reduces the ability to respond to neoantigens and may compromise the life of infected individuals. Here, we analyzed the immunological memory to SARS-CoV-2 in 102 recovered patients aged over 60 years several months after the infection had been resolved. Specific memory T lymphocytes against the virus were measured by interferon-γ (IFN-γ) and granzyme B release by ELISpot; memory B-lymphocyte responses were quantified by detection of anti-S IgG1 producer cells by ELISpot and anti-S and anti-N antibodies were determined by enzyme-linked immunosorbent assay (ELISA). Memory T lymphocytes were found in peripheral blood of most of the studied donors, more than 7 months after the infection in some of them. Fewer patients maintained memory B lymphocytes, but antibodies, mainly anti-S, were highly durable and positively correlated with T responses. More robust humoral responses were found in patients who had more severe symptoms and had been admitted to hospital. We concluded that specific immunity against SARS-CoV-2 is effectively preserved regardless of age, despite the great heterogeneity of their immune responses, and that memory T lymphocytes and anti-S IgG might be more durable than memory B cells and anti-N IgG.
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Anticuerpos Antivirales/inmunología , COVID-19 , Inmunidad Celular/fisiología , Inmunidad Humoral , Memoria Inmunológica , SARS-CoV-2 , Anciano , Anciano de 80 o más Años , Ensayo de Immunospot Ligado a Enzimas , Femenino , Humanos , Inmunoglobulina G , Masculino , Células B de Memoria , Células T de Memoria , Persona de Mediana EdadRESUMEN
The exquisite coupling between herpesvirus and human beings is the result of millions of years of relationship, coexistence, adaptation, and divergence. It is probably based on the ability to generate a latency that keeps viral activity at a very low level, thereby apparently minimising harm to its host. However, this evolutionary success disappears in immunosuppressed patients, especially in haematological patients. The relevance of infection and reactivation in haematological patients has been a matter of interest, although one fundamentally focused on reactivation in the post-allogeneic stem cell transplant (SCT) patient cohort. Newer transplant modalities have been progressively introduced in clinical settings, with successively more drugs being used to manipulate graft composition and functionality. In addition, new antiviral drugs are available to treat CMV infection. We review the immunological architecture that is key to a favourable outcome in this subset of patients. Less is known about the effects of herpesvirus in terms of mortality or disease progression in patients with other malignant haematological diseases who are treated with immuno-chemotherapy or new molecules, or in patients who receive autologous SCT. The absence of serious consequences in these groups has probably limited the motivation to deepen our knowledge of this aspect. However, the introduction of new therapeutic agents for haematological malignancies has led to a better understanding of how natural killer (NK) cells, CD4+ and CD8+ T lymphocytes, and B lymphocytes interact, and of the role of CMV infection in the context of recently introduced drugs such as Bruton tyrosine kinase (BTK) inhibitors, phosphoinosytol-3-kinase inhibitors, anti-BCL2 drugs, and even CAR-T cells. We analyse the immunological basis and recommendations regarding these scenarios.
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Infecciones por Citomegalovirus/inmunología , Citomegalovirus/fisiología , Neoplasias Hematológicas/inmunología , Trasplante de Células Madre Hematopoyéticas , Activación Viral/inmunología , Aloinjertos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/terapia , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/virología , Humanos , Células Asesinas Naturales/inmunología , Trasplante Autólogo , Trasplante HomólogoRESUMEN
High levels of inflammation play an important role in chronic heart failure (CHF). Patients with CHF have elevated levels of pro-inflammatory cytokines circulating systemically, mainly TNF and IL-6. However, there are almost no studies that relate these levels to the functional status of patients in CHF, much less to their CMV serostatus. In this study, patients with CHF (n=40; age=54.9 ± 6.3; New York Heart Association functional classification (NYHA, I-III) and healthy controls (n=40; age=53.5 ± 7.1) were analyzed. The serum concentrations of nine pro- and anti-inflammatory cytokines were measured by Luminex® xMap Technology and the basal level of mRNA expression of some immune molecules was quantified by TaqMan™ Array in CD4+ T-lymphocytes. The concentration of these cytokines in culture supernatants in response to anti-CD3 and LPS was also measured. The percentage of CD28null T-cells was determined, as well as the antibody titer against CMV. We found a higher concentration of all cytokines studied in CHF serum compared to healthy controls, as well as a direct correlation between functional status in CHF patients and levels of inflammatory cytokines. Moreover, the highest cytokine concentrations were found in patients with higher concentrations of lymphocytes lacking CD28 molecule. The cytokine production was much higher in CMV+ patients, and the production of these cytokines was found mainly in the T-lymphocytes of CMV+ patients in response to anti-CD3. Anti-CMV antibody levels were positively correlated with cytokine levels. The baseline expression of specific mRNA of the main molecules involved in the Th1 response, as well as molecules related to the CD4+CD28 null subset was higher in CMV+ patients. The cytokine concentrations are higher in CHF CMV+ patients and these concentrations are related to the production of antibodies against CMV. These high levels of cytokines are also associated with the more differentiated CD28null lymphocyte populations. All this, together with the dynamics of the pathology itself, makes CMV+ patients present a worse functional status and possibly a worse evolution of the pathology.
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Linfocitos T CD4-Positivos/inmunología , Citocinas/sangre , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Insuficiencia Cardíaca/inmunología , Mediadores de Inflamación/sangre , Inflamación/inmunología , Anticuerpos Antivirales/sangre , Biomarcadores/sangre , Antígenos CD28/deficiencia , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/virología , Estudios de Casos y Controles , Enfermedad Crónica , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/virología , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Interacciones Huésped-Patógeno , Humanos , Inflamación/sangre , Inflamación/diagnóstico , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
Expanded CD4+CD28null T lymphocytes are found in the tissues and peripheral blood of patients with many autoimmune diseases, such as rheumatoid arthritis (RA). These highly differentiated cells present potent inflammatory activity and capability to induce tissue destruction, which has been suggested to predispose to the development of more aggressive disease. In fact, preferential migration to inflammatory sites has been proposed to be a contributing factor in the progression of autoimmune and cardiovascular diseases frequently found in these patients. The functional activity of CD4+CD28null T lymphocytes is largely dependent on interleukin 15 (IL-15), and this cytokine may also act as a selective attractor of these cells to local inflammatory infiltrates in damaged tissues. We have analysed, in RA patients, the migratory properties and transcriptional motility profile of CD4+CD28null T lymphocytes compared to their counterparts CD28+ T lymphocytes and the enhancing role of IL-15. Identification of the pathways involved in this process will allow us to design strategies directed to block effector functions that CD4+CD28null T lymphocytes have in the target tissue, which may represent therapeutic approaches in this immune disorder.
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BACKGROUND: Diagnosis of hematolymphoid neoplasm (HLN) requires different technologies which are performed on a patient basis instead of per protocol. We hypothesize that integration of hematimetric and cytological analysis along with multiparametric flow cytometry (MFC) provides a framework to evaluate peripheral blood (PB) samples from Primary Care. METHODS: Samples from patients with persistent (>3 months) lymphocytosis (>5 × 109/L) and/or monocytosis (>109/L) or the presence of atypical and/or blast cells upon the smear review were analyzed by MFC concurrent to cytological analysis. MFC studies were carried out following standardized procedures. RESULTS: In a 3-year period, smear review and MFC were performed simultaneously in 350 samples, demonstrating HLN in 194 cases (55.4%). In 156 cases, reactive cell populations were found. The combination of age, absolute lymphocyte count (ALC), hemoglobin and platelets provided the best correlation with MFC for the presence of a chronic lymphoproliferative disorder (CLPD) in lymphocytosis [area under the curve (AUC) 0.891, p < 0.05]. A model evaluating the probability of CLPD has been proposed and validated in an independent cohort. CONCLUSIONS: A strategy to perform MFC studies following standardized procedures has proven to be useful to evaluate samples from patients in Primary Care centers for HLN diagnosis or reactive conditions, providing a sensitive and rapid clinical orientation and avoiding unnecessary consultations in routine clinical practice. The probability for the presence of CLPD in PB can be calculated and help guide decision-making regarding further testing.
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Linfocitosis , Trastornos Linfoproliferativos , Neoplasias , Algoritmos , Humanos , Linfocitosis/diagnóstico , Atención Primaria de SaludRESUMEN
Introduction: Cryopreserved arterial allografts have remained an option in patients requiring distal revascularization or associated with vascular infection, in the absence of a valid autogenous saphenous vein. The objective of this study is to describe the different clinical, anatomopathological, and immunological findings related to vascular transplant rejection. Methods: In a prospective trial, 35 patients who underwent cryopreserved allogeneic arterial bypass were studied, including demographics and conduit patency. Anti-HLA antibody production was stablished prior to the surgery, 7 days, 1, 3 months, and every 3 months since. Clinical and ultrasound evaluation was added after the first month. Donor HLA-typing was retrieved whenever available, allowing for the characterization and quantification of donor specific antibodies. Cytotoxic crossmatch test was also performed. A second group of patients with allograft degenerations registered during the follow up period was studied. In this group, exclusively for aneurysm description and histopathological analysis, they were included those degenerated vascular transplants from the original series, but also those implanted prior to the beginning of the study and degraded during follow up. Results: All patients studied displayed an increase in anti-HLA antibodies one month after the intervention, regarding bypass patency. In total, 14 patients fulfilled requirements for the study of donor specific antibodies, equally showing IgG production detectable one month after surgery. The presence of complement-fixing antibodies was also confirmed. Antibody levels were not related to graft degeneration. No specific immune markers able to predict aneurysmal development and evolution were found. From the original group, 3 patients suffered aneurysmal degeneration during follow up, together with 9 bypasses previously implanted. Average time until the first degeneration was 33 ± 19.7 months, with 30.6 ± 17.7 and 54.5 ± 2.5 months for a second and third degeneration, when occurring. Therefore, subsequent vascular transplants frequently augmented the time for new degenerations, despite increasing sensibilization. Samples from eight degenerated allografts were available for analysis, unexpectedly showing inflammatory infiltrate in only four cases and immune complex deposition in 7. Conclusions: Immune response against vascular transplants was confirmed in all cases, but chronic rejection did not necessarily provoke bypass degradation or reduced the time for new aneurysms to develop in subsequent allografts.
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There are strong evidences that probiotics influence the immune status of the host, in a strain-specific manner, acting in the gastrointestinal tract. On the hypothesis that certain extracellular proteins and peptides from gut bacteria may mediate part of this immunomodulation and assuming they are able to diffuse through the mucus layer and interact with immune cells we have developed this work. Our study attempts to understand the immunomodulatory mechanisms of (i) Pext, the extracellular protein fraction of Lactobacillus acidophilus DSM20079T, (ii) HM14, a peptide encrypted in an extracellular glycoside hydrolase from Bifidobacterium longum NCIMB 8809 and (iii) Escherichia coli O111:B4 lipopolysaccharide (LPS), a well-known pro-inflammatory molecule, over human peripheral blood mononuclear cells (PBMCs). An untargeted LC-ESI-QTOF-MS metabolomics approach was applied to reveal intracellular changes in treated-PBMCs isolated from healthy donors. Differences in NADH arrest, NAD+ concentration reduction, as well as increases in palmitic acid and methanephrin were observed in HM14 and Pext treated-cells compared to those stimulated with LPS. This would support an anti-inflammatory molecular mechanism of action of such proteinaceous molecules. Moreover, this methodology has confirms the importance of metabolomics approaches to better understanding immune cell responses to gut bacterial-derived molecules.
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RATIONALE: The tuberculin skin test (TST) and interferon ? release assays (IGRAs) are commonly used for latent tuberculosis infection (LTBI) screening. Unexpectedly high TST positivity rates have been reported in patients with rheumatic diseases, and methotrexate is frequently used in this population. We hypothesized that methotrexate use could be associated with false-positive TST results. OBJECTIVES: To investigate whether treatment with methotrexate and other factors are associated with false-positive TST results in patients with rheumatic diseases. METHODS: Prospective single-center study conducted between April 2013 and March 2016. Adult patients with rheumatic diseases were evaluated with a TST and two IGRAs for LTBI screening. We compared TST and IGRA results in patients treated and not treated with methotrexate and analyzed for factors associated with positive TST results. CONCLUSIONS: Our data suggest false-positive TST results associated with methotrexate therapy. Thus, we recommend against using the TST for LTBI screening in patients receiving methotrexate and the preferential use of IGRAs in such patients. MEASUREMENTS AND MAIN RESULTS: We studied 393 patients with rheumatic diseases, including ankylosing spondylitis (ASP, n = 90), rheumatoid arthritis (RA; n = 120), psoriatic arthritis (PA, n = 126), and other disorders (n = 57). The rate of TST positivity varied across the groups: ASP 22.2%, RA 25%, PA 35.7%, and other disorders (22.8%). Positivity rates were lower with IGRAs. Methotrexate use was associated with a statistically significant two-fold increase in the risk of a positive TST and a dose\x96 response relationship was observed. We found no statistically significant associations between methotrexate use and IGRA test positivity.
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Tuberculosis Latente/diagnóstico , Metotrexato/uso terapéutico , Enfermedades Reumáticas/tratamiento farmacológico , Adulto , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prueba de TuberculinaRESUMEN
Glucose, chief metabolic support for cancer cell survival and growth, is mainly imported into cells by facilitated glucose transporters (GLUTs). The increase in glucose uptake along with tumor progression is due to an increment of facilitative glucose transporters as GLUT1. GLUT1 prevents cell death of cancer cells caused by growth factors deprivation, but there is scarce information about its role on the damage caused by glucose deprivation, which usually occurs within the core of a growing tumor. In prostate cancer (PCa), GLUT1 is found in the most aggressive tumors, and it is regulated by androgens. To study the response of androgen-sensitive and insensitive PCa cells to glucose deprivation and the role of GLUT1 on survival mechanisms, androgen-sensitive LNCaP and castration-resistant LNCaP-R cells were employed. Results demonstrated that glucose deprivation induced a necrotic type of cell death which is prevented by antioxidants. Androgen-sensitive cells show a higher resistance to cell death triggered by glucose deprivation than castration-resistant cells. Glucose removal causes an increment of H2O2, an activation of androgen receptor (AR) and a stimulation of AMP-activated protein kinase activity. In addition, glucose removal increases GLUT1 production in androgen sensitive PCa cells. GLUT1 ectopic overexpression makes PCa cells more resistant to glucose deprivation and oxidative stress-induced cell death. Under glucose deprivation, GLUT1 overexpressing PCa cells sustains mitochondrial SOD2 activity, compromised after glucose removal, and significantly increases reduced glutathione (GSH). In conclusion, androgen-sensitive PCa cells are more resistant to glucose deprivation-induced cell death by a GLUT1 upregulation through an enhancement of reduced glutathione levels.
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Transportador de Glucosa de Tipo 1/genética , Estrés Oxidativo/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Superóxido Dismutasa/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Glucosa/metabolismo , Transportador de Glucosa de Tipo 1/metabolismo , Glutatión/metabolismo , Humanos , Peróxido de Hidrógeno/química , Masculino , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/genética , Superóxido Dismutasa/metabolismoRESUMEN
Anti-CMV (cytomegalovirus) antibody titers are related to immune alterations and increased risk of mortality. To test whether they represent a marker of infection history, we analyzed the effect of viral reactivations on the production of specific antibodies in kidney transplant patients. We quantified CMV-DNAemia and antibody titers in 58 kidney transplant patients before transplantation and during a follow-up of 315 days (standard deviation, SD: 134.5 days). In order to calculate the intensity of the infection, we plotted the follow-up time of the infection on the x-axis and the number of DNA-CMV copies on the y-axis and calculated the area under the curve (CMV-AUC). The degree of T-lymphocyte differentiation was analyzed with flow cytometry, the cells were labelled with different monoclonal antibodies in order to distinguish their differentiation state, from naive T-cells to senescent T-cells. Peak viremia was significantly higher in patients experiencing a primary infection (VI) compared to patients experiencing viral reactivation (VR). Our data indicate that the overall CMV viral load over the course of a primary infection is significantly higher than in a reactivation of a previously established infection. Whereas patients who experienced an episode of CMV reactivation during the course of our observation showed increased levels of CMV-specific antibodies, patients who did not experience CMV reactivation (WVR) showed a drop in CMV antibody levels that corresponds to an overall drop in antibody levels, probably due to the continuing immunosuppression after the renal transplant. We found a positive correlation between the CMV viremia over the course of the infection or reactivation and the CMV-specific antibody titers in the examined patients. We also observed a positive correlation between anti-CMV titers and T-cell differentiation. In conclusion, our data show that anti-CMV antibody titers are related to the course of CMV infection in kidney transplant patients.
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Anticuerpos Antivirales/sangre , Infecciones por Citomegalovirus/inmunología , Fallo Renal Crónico/complicaciones , Trasplante de Riñón/efectos adversos , Activación Viral , Adulto , Anciano , Área Bajo la Curva , Linfocitos T CD8-positivos/inmunología , Citomegalovirus , ADN Viral , Femenino , Estudios de Seguimiento , Antígenos HLA/inmunología , Humanos , Inmunofenotipificación , Terapia de Inmunosupresión , Fallo Renal Crónico/cirugía , Fallo Renal Crónico/virología , Masculino , Persona de Mediana Edad , Carga Viral , Viremia/tratamiento farmacológicoRESUMEN
Immunosenescence in chronic heart failure (CHF) is characterized by a high frequency of differentiated T-lymphocytes, contributing to an inflammatory status and a deficient ability to generate immunocompetent responses. CMV is the best known inducer of T-lymphocyte differentiation, and is associated with the phenomenon of immunosenescence. In this study, we included 58 elderly chronic heart failure patients (ECHF), 60 healthy elderly controls (HEC), 40 young chronic heart failure patients (YCHF) and 40 healthy young controls (HYC). High differentiation of CD8+ T-lymphocytes was found in CMV-seropositive patients; however, the differentiation of CD4+ T-lymphocytes was increased in CMV-seropositive but also in CHF patients. Anti-CMV antibody titers showed positive correlation with more differentiated CD4+ and CD8+ subsets and inverse correlation with CD4/CD8 ratio. Immunosenescence found in CHF patients is mainly due to the dynamics of CMV-infection, since the differentiation of T-lymphocyte subsets is related not only to CMV-infection, but also to anti-CMV antibody titers.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Insuficiencia Cardíaca/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/inmunología , Relación CD4-CD8 , Linfocitos T CD4-Positivos/patología , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/virología , Enfermedad Crónica , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/virología , Femenino , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/virología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
T lymphocytes, from their first encounter with their specific antigen as naïve cell until the last stages of their differentiation, in a replicative state of senescence, go through a series of phases. In several of these stages, T lymphocytes are subjected to exponential growth in successive encounters with the same antigen. This entire process occurs throughout the life of a human individual and, earlier, in patients with chronic infections/pathologies through inflammatory mediators, first acutely and later in a chronic form. This process plays a fundamental role in amplifying the activating signals on T lymphocytes and directing their clonal proliferation. The mechanisms that control cell growth are high levels of telomerase activity and maintenance of telomeric length that are far superior to other cell types, as well as metabolic adaptation and redox control. Large numbers of highly differentiated memory cells are accumulated in the immunological niches where they will contribute in a significant way to increase the levels of inflammatory mediators that will perpetuate the new state at the systemic level. These levels of inflammation greatly influence the process of T lymphocyte differentiation from naïve T lymphocyte, even before, until the arrival of exhaustion or cell death. The changes observed during lymphocyte differentiation are correlated with changes in cellular metabolism and these in turn are influenced by the inflammatory state of the environment where the cell is located. Reactive oxygen species (ROS) exert a dual action in the population of T lymphocytes. Exposure to high levels of ROS decreases the capacity of activation and T lymphocyte proliferation; however, intermediate levels of oxidation are necessary for the lymphocyte activation, differentiation, and effector functions. In conclusion, we can affirm that the inflammatory levels in the environment greatly influence the differentiation and activity of T lymphocyte populations. However, little is known about the mechanisms involved in these processes. The elucidation of these mechanisms would be of great help in the advance of improvements in pathologies with a large inflammatory base such as rheumatoid arthritis, intestinal inflammatory diseases, several infectious diseases and even, cancerous processes.